Mobile railway ballast tamping machine with track lifting mechanism



Allg 19, 1958 F. PLAssER ET AL 2,847,943

MOBILE RAILWAY BALLAST TAMPING MACHINE: WITH TRACK LIFTING MEcHANIsM Filed oct. 1s, 1956,`

INVENTRS Franz PLSSEQJ'asEp BY @LA 2,847,943 Patented Aug. 19, 1958 Unitedv States Patent Oilice MOBILE RArLWAYtBALLAs-r rAMrrNGMAcHlNE wrrH TRACK LIFTING MECHANISM Franz Plasser and Josef Theurer, Vienna, Austria Application October 18, 1956, Serial-No. 616,697 Claims priority, application Austria October 2 5, 1955 4 Claims.` (Cl; 10ft- 12) The present invention relates tomobile ballast tamping machines, andnrore particularly to attack liftingim'echanism mounted at the front endof the machine.

Mobile ballast tamping machinesv with tamping tool carriers overhanging the tie to betamped are known. The entire weight of such machines rests: on the tamped ties while the forward end of the machineissuspended over the tamping area and noV weightpresses" on the ties while they are tamped. The present inventionis particularly` effective with this type of tamping machine.

In railroad bed maintenance, ballast tamping operations usually proceed a-s follows.: rst, a surveying crew makes the necessary measurements and marks the ties, for instance with chalk, to show vhow much. each tie mustbe lifted by tamping to Abring it into-thecorrectposition. Then, another crew :is sent outto-lifteachtiewith hand tools, according to the surveyors marks, and to x the ties provisionally in` their desired position 'byl placing ballast thereunder. After the trackjhas been thus prepared, a mobile ballast tamping machine is operated over the track to effect the tamping operation proper.

It is the principal object of the present invention to simplify railroad'tracktamping and to make it more efcient and economical.

It is a concomitant object ofthis invention to provide automatic means `on4 the'tamping machine itself for, li'ftingthe track to-the desired position and hold it in such position during tamping by the machine.

In accordance with the invention, a track lifting mechanismismounted atr the front end o'f the track tamping machine to vlift the trackl to the desired position before tamping.. starts, suchI track` lift-ing1.-mecliafn`ism being partcularly applicable to machines of the type where the tamping tool carrier is mounted in a frame jutting out from the carriage in front of the front wheels. In such a machine, the track lifting mechanism engages the track ahead of the tie to be tamped and can lift the track suflciently to hold the tie to be tamped in the desired position, the entire track portion on which work is being done remaining free of any load. On the other hand, no portion of the track which has already been tamped will be lifted since the tamped track portion is held down by the weight of the machine which rests thereon with its wheels.

According to a preferred feature of the invention, the track lifting mechanism comprises a vertically adjustable iluid pressure operated clamping or gripping device. Hydraulic operation of the vertical adjustment aswell as of gripping device may comprise two pivotally connected clamping jaws which are hydraulically operated. The device is preferably so constructed that the jaws are adapted to grip the rail head but, if desired, the jaws could also grip the ties themselves. Preferably, the hydraulic means for operating the gripping jaws includes a hydraulic cylinder pivoted to one of the jaws and a cooperating piston pivoted to the other jaw, the piston and cylinder being mounted below the hinge means connecting the jaws.

For vertical adjustment of the gripping or clamping jaws, the jaws are preferably mounted on a piston rod operating in a cylinder under the influence of fluid pressure, such as hydraulic pressure. The piston divides the cylinder into two chambers and, particularly in machines operating with vibrating tamping tools, it is advantageous to minimize or prevent vibration ofthe lifted track by applying iluid pressure 'to both cylinder chambers, thus holding the piston in rigid position by applying pressure thereto from above and from below.

The above and other objects, features and advantages of the present invention will be more fully explained in connection with a now preferred embodiment described in det-ail in conjunction with the accompanying drawing wherein Fig. 1 schematically illustrates a mobile ballast tamping machine with suspended tamping tool carrier and a track lifting mechanism mounted at its front end; and

Fig. 2 is a side view, partly in section, of the track lifting device.

The present invention is' not concerned with the ballast tamping machine per se and its structure is, therefore, only schematically shown. One such machine, with various modifications, has been described and claimed, for instance, in our U. S; patent application Serial No. 462,086, filed October 13, 1954. However, the present invention `isin no way limited to the specific tamping apparatus. disclosed in our prior application.

Referring 'now to ther drawing, mobile track tamping machine 1 running on track llvcarries vertically adjustable tamping tool carrier 2 suspended above the tie to bei tamped. This structure isknown per se and forms no part of.' the present invention, except in combination with the track lifting mechanism to be described hereinafter.

`At the front endV of the machine (fviewed in the direction of travel), there is` mounted the track lifting mechanism more fully shown in Fig. 2. As appears from Fig. l, the track lifting mechanism is-above tie 16 when tamping tool carrier 2 is in position 'tot tamp tie 16. Howeverssincethere is no load on tie 16, this tie will be lifted with tie 16* whilev the previously tampedv ties '(to the left of -16 in Fig. l) will remainn position due tothe loadof machinedV which rests thereon.`

The track lifting mechanism. comprises essentially a lluid pressurecylinder''with.lluid conduits 4 andS and piston 6. Preferably, lluid, such as hydraulic lluid, is supplied to both chambers in the cylinder to apply pressure against both sides of the piston and to hold it in rigid position against the vibration of the suspended front portion of the machine during tamping. Piston rod '7' eX- tends outside the cylinder and has fixed to its free end a pivot 14 mounting gripping or clamping jaws 8 and 9 in the manner of pliers. The outer ends of the jaws are provided with friction lining 10 adapted to firmly engage the head of rail 11. When the rail is gripped and held by jaws 8, 9, it will not be subjected to any substantial vibration even while the vibrating tamping tools operate. This will eliminate any damaging influence of Vibrations on the track portion which has already been tamped.

To operate the clamping or gripping jaws 8, 9, iluid pressure cylinder 12 is pivoted to jaw 8 and cooperating piston 13 is pivoted to jaw 9. Fluid, such as hydraulic fluid, is supplied to cylinder 12 by iluid conduit 15.

The machine operates as follows:

When it is desired to re-position tie 16 and to tamp the tie, the mobile track tamping machine is moved into the position shown in Fig. l (with tamping tool carrier 2 lifted above the tracks, as is well known). The lluidcontrolled track lifting mechanism is then operated to lower it into position to grip rail 11, the jaws being closed by suitable lluid supply to cylinder 12. When the rail is rmly gripped, fluid is supplied to cylinder 3 to lift the rail until tie 16 is in the desired position. Preferably, additional fluid is subsequently supplied to the other chamber in cylinder 3 to hold the piston 6 in rigid position. Thereupon, tamping tool carrier 2 is lowered into tamping position and the tamping operation is initiated in a manner known per se.

As will be clear from the above description of the structure and operation of the machine, the invention permits not only a considerable economy in labor and time, inasmuch as the work crew which provisionally prepares the track for tamping is entirely eliminated, but it also assures a considerably improved and more accurate operation since each track portion is rigidly held in the correct position during tamping itself. Thus, the track which was previously put in the desired position cannot be moved during tamping, as was the case in the prior procedure involving manual preparation of the track.

The automatic track lifting mechanism may be further improved and its operation made speedier and more accurate if control means is provided in the fluid conduit to meter the fluid supply automatically in accordance with the height to which the track is to be lifted. For instance, the operator may simply look at the surveyors mark indicating the height to which the tic is to be lifted and adjust the control means accordingly, whereupon he actuates the fluid supply means to supply a metered amount of lluid to the cylinder and cause the gripping jaws to be lifted to the desired height.

While the invention has been described and illustrated in connection with a preferred embodiment thereof, many changes of a mechanical nature may occur to the skilled in the art, particularly after benefiting from the present teaching, without departing from the spirit and scope of the invention as defined in the appended claims. More particularly, the structure of the rail gripping means as well as the lifting means may be varied. For instance, while fluid pressure control, preferably hydraulic pressure, will assure most accurate and dependable operation, mechanical means, such as screw, gear, or ratchet drives, for instance, may be used to actuate the lifting and/or gripping means.

What is claimed is:

l. A mobile railway ballast tamping machine having wheels including front wheels for mobility on a track and comprising a freely suspended front end portion ahead of said front wheels, a tamping tool carrier mounted in said front end portion to be positioned above a tie to be tamped, a track lifting means for lifting the track for- Wardly of said front wheels relatively to the machine resting stationary on the track, said lifting means being mounted at the front end of said portion and ahead of said tamping tool carrier, and means for actuating the mechanism for lifting the track to a predetermined height.

2. The tamping machine of claim 1, wherein the track lifting means comprises a fluid pressure cylinder mounted at the front end of the machine, a piston slidably movable in said cylinder and dividing the cylinder into two chambers, uid conduit means connected to the cylinder, a piston rod having one end fixed to the piston and another end extending outside of the cylinder, and track gripping means connected to said other piston rod end.

3. A mobile railway ballast tamping machine comprising a freely suspended front end portion, a tamping tool carrier mounted in said front end portion to be positioned above a tie to be tamped, and a track lifting mechanism including a fluid pressure cylinder mounted at the front end of the said portion and ahead of said tamping tool carrier, a piston slidably movable in said cylinder and dividing the cylinder into two chambers, uid conduit means connected to the cylinder for applying fluid pressure against the piston, a piston rod having one end fixed to the piston and another end extending downwardly outside of the cylinder, and Huid-pressure controlled track gripping means connected to said other piston rod end.

4. The ballast tamping machine of claim 3, wherein the track gripping means comprises two pivotally connected gripping or clamping jaws, a uid pressure cylinder pivotally connected to one jaw and a piston pivotally connected to the other jaw, the piston sliding in the cylinder to actuate the jaws by uid pressure.

References Cited in the le of this patent UNITED STATES PATENTS 1,346,160 Barlow July 13, 1920 2,482,111 Jackson Sept. 20, 1949 2,554,433 Warren May 22, 1951 2,596,823 Richardson May 13, 1952 2,696,971 Philbrick Dec. 14, 1954 2,734,463 Hursh et al Feb. 14, 1956 2,757,037 Troyer July 31, 1956 FOREIGN PATENTS 1,101,408 France Apr. 20, 1955 324,146 Germany Aug. 25, 1920 349,163 Germanyv Feb. 24, 1932 

